The present invention relates generally to an air compressor system and more particularly to an air/oil separator tank for use with an oil-flooded air compressor.
In conventional air compressor systems which utilize an oil-flooded compressor, air is compressed in a compression chamber or airend by a set of rotary screws, and a lubricant, such as oil, is injected into the compression chamber and mixes with the compressed air. The oil is generally injected into the compression chamber for a number of reasons including cooling the air compressor system, lubricating bearings, balancing axial forces and sealing the rotary screws. Although using oil is essential for operating these types of air compressor systems, the oil must be removed from the stream of compressed air before the compressed air may be used downstream for pneumatic equipment and/or other tools.
Thus, in such conventional air compressor systems, the compressed air and oil mixture discharged from the airend of the compressor flows with a high velocity into a separator tank where the air and oil of the air/oil mixture are caused to separate. The separator tank is usually cylindrical and the air/oil mixture is directed around an inner wall of a separation chamber. The combination of the centrifugal forces acting on the air/oil mixture and contact between the air/oil mixture and the inner wall of the separation chamber causes much of the oil to separate from the air/oil mixture, thereby allowing gravity to draw the oil downwardly into a lower portion of the separation chamber and also allowing the air to separate from the oil and flow upwardly in the separation chamber. This type of separation effect is known in the art as primary separation.
As generally known, an air/oil separator tank for an oil-flooded air compressor system generally provides two functions. The separator tank provides a means to separate oil from the air/oil mixture introduced into the separation chamber as described above and it also functions as an oil sump for the compressor system.
Conventional air compressor systems as described above include multiple hoses, tubes, pipes or the like and associated fittings connecting a compressor to a separator tank. Hoses and associated fittings provide potential leak paths which, if developed, could adversely affect the overall operation of the compressor system. Using hoses and associated fittings also requires additional assembly time. Thus, there is a need for an air compressor system which eliminates or at least reduces the number of hoses and associated fittings used to connect a compressor to a separator tank.
As commonly understood, conventional air compressor systems as described above include a motor or drivetrain to operate the compressor. Since conventional air compressor systems use a hose, typically a flexible hose, to connect the compressor to a separator tank, the drivetrain, the compressor and the separator tank are not securely attached as a single unit, thereby making it virtually impossible to maneuver the entire compressor system as one. In addition, since the compressor and the separator tank are individual units, each is provided with its own isolation or supporting mounts, thereby adding undesirable cost to the overall compressor system. Thus, there is a need for an air compressor system which is easier to handle and which is assembled together in such a way that the entire compressor system can be handled or moved as a single unit, and which is also mountable to an associated subbase, so as to provide a more cost effective compressor system.
Conventional air compressor systems as described above may include a baffle element strategically placed within a separation chamber of a separation tank to inhibit the migration of oil separated from the air/oil mixture introduced into the separation chamber from undesirably migrating upwardly into an upper portion of the separation chamber. However, such a baffle element adds to the overall cost of the compressor system and increases the assembly time associated with the compressor system. Thus, there is a need for an air compressor system which does not require the use of a baffle element and which still inhibits the migration of oil separated from the air/oil mixture introduced into the separation chamber from undesirably migrating upwardly into the upper portion of the separation chamber.
The present invention provides in one aspect thereof, a cast separator tank having an airend inlet opening which is directly mountable to an airend discharge opening of a compressor. The construction of the invention eliminates any need for a hose and associated fittings to connect the airend discharge opening of the compressor to the airend inlet opening of the separator tank.
The present invention provides in another aspect thereof, a cast separator tank having an integrally cast channel extending between an airend inlet opening and a separation chamber. An air/oil mixture discharged from a compressor enters the airend inlet opening and flows through the channel into the separation chamber. The integrally cast channel further eliminates the need for associated hoses and fittings between the compressor and the separator tank.
In one embodiment, a cast separator tank includes an integrally cast member which surrounds the airend inlet opening and which is positioned beneath the airend discharge opening of the compressor, so as to support the end of the compressor which houses the airend discharge opening of the compressor. In one aspect of the present invention, a drivetrain for operating the compressor is provided with a mounting foot and the separator tank is provided with an integrally cast mounting foot. The integrally cast member of the separator tank that supports the end of the compressor which houses the airend discharge opening of the compressor provides a third mounting foot. Because the compressor and the separator tank are directly attached to one another and the motor is directly secured to the compressor, the entire compressor system can be moved as a single unit. The mounting feet are conveniently attached to a support base in a chosen location.
The present invention provides in another aspect thereof, a cast separator tank having an integrally cast channel which is in fluid flow communication with a lower portion of a separation chamber and which extends along an outer surface of the separator tank. Oil separated from an air/oil mixture introduced into the separation chamber collects in the lower portion of the separation chamber. Pressure within the separation chamber causes the oil to flow into the channel and out of the separation chamber. Because the channel is integrally cast with the separator tank, there is no need for a hose and fitting device to enable the oil to flow out of the lower portion of the separation chamber.
In another embodiment, a cast separator tank includes an integrally cast lip which extends circumferentially around an inner wall of a separation chamber between an upper and a lower portion of the separator chamber. The integrally cast lip inhibits oil in an air/oil mixture introduced into the separation chamber from migrating up into the upper portion of the separation chamber when the air/oil mixture is directed around an inner wall of the separation chamber and subjected to centrifugal forces. Because the lip is integrally cast with the tank, the use of a baffle element is not required.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features.